Cuprous alloy



Patented Aug. 20, 1940 PATENT OFFICE CUPROUS ALLOY James Fletcher, Detroit, Mich.

No Drawing. Application January 5, 1940, Serial No. 312,574

4 Claims.

The present invention relates to alloys and more particularly to cuprous alloys or alloys in which copper is the predominant metal. Among the objects of the invention is an alloy which, while differing materially in some respects from copper yet preserves to a high degree its conductivity characteristics.

Another object is an alloy which is predominantly copper but which, though much harder is more workable, being capable of considerable working without annealing.

The above results and other very desirable ones are obtained by alloying with electrolytic copper a small percentage of each of the following elements: chromium, silicon, and magnesium.

An example of the proportions of the several elements to be alloyed, is as follows:

Per cent Chromium .1 to 1. Silicon .02 to .2 Magnesium .05 to .5

the balance of being copper.

The preferred composition and one that gives superior results is as follows:

Per cent Chromium .4 Silicon .08 Magnesium 4 balance copper.

An alloy of the above composition is capable of considerable cold working without cracking and is, after heat treatment, well adapted for use in making such articles as welding electrodes,-being quite hard and, because of its high conductivity, requiring less electric current than many alloys heretoforeused.

While the preferred proportions are given above, these may of course be varied to some extent. If a greater proportion of the non-cuprous constituents is used, the resulting alloy is increased in hardness but the conductivity is lessened.

For example, in an alloy in which the lower given percentages of magnesium, silicon and chromium are used, the Brinell test will show a hardness of about while the higher percentages may run the Brinell hardness up to as high as 160.

The conductivity of such compositions will range from about 90% down to 75%.

In all cases the relative percentages of the three non-cuprous constituents should be about as given in the preferred composition.

Now, having described the invention and the preferred form of embodiment, what I claim is:

1. An alloy consisting of copper containing chromium, silicon, and magnesium, the combined percentages of the non-cuprous elements being between 0.15 and 2.00, and their relative proportions substantially one of silicon, five of chromium, and two of magnesium.

2. An alloy having substantially the followin composition:

Per cent Chromium .4 Silicon .08 Magnesium .14

the remainder being copper.

composition:

, Per cent Chromium .1 to 1. Silicon .02 to 2. Ma,gnesium .05 t0 .5

the remainder being copper.

JAMES FLETCHER. 

